1. Field of the Invention
The present invention relates to a power factor correction apparatus capable of correcting a power factor of a power source device, and a method for controlling a power factor using the same.
2. Description of the Related Art
Recently, national governments around the world have urged the effective use of energy in conformity with energy efficiency policies, and in particular, effective use of energy in electronic products or home appliances is widely recommended.
Thus, according to such recommendations, a remedial circuit for effectively using energy has been applied to power supply devices supplying power to electronic products, home appliances, and the like.
The remedial circuit may be, for example, a power factor correction circuit. A power factor correction circuit is a circuit for switching input power to adjust a phase difference (power factor) between a current and a voltage of the input power to effectively transfer power to a rear stage.
Among power factor correction circuits, a boost power factor correction circuit has been generally used, but it have relatively low efficiency, a high internal current, voltage ripples, electromagnetic interference (EMI) noise, and the like, and thus, so its application to a middle or large-scale power source device is not easy.
In order to solve these problems, in case of a related art interleaved boost power factor correction (PFC) circuit configured by connecting boost PFC circuits in parallel, the respective boost PFCs connected in parallel are equally operated with a time difference during a switching period with respect to overall output power, to thereby simultaneously reduce ripples of an input current and those of an output voltage. Accordingly, a size of an input EMI filter can be reduced.
However, the interleaved boost PFC circuit has a limitation in that degradation of a power factor due to a phase difference between inductors connected in parallel cannot be compensated. In other words, a phase difference between inductors cannot be compensated.
The related art mentioned below relates to a power factor correction circuit, which, however, has the foregoing limitations.